1. Field of the Invention
The present invention relates to a composition for forming a light-shielding layer that has excellent light-shielding properties and which is useful in the field where non-conductivity is required. More specifically, the present invention relates to a composition for forming a non-conductive light-shielding layer, useful for making the light-shielding layer (black matrix) of a color filter to be used for liquid crystal displays or the like, to a non-conductive light-shielding layer made from the composition, and to a color filter comprising the light- shielding layer.
2. Background Art
It has conventionally been known that either a light-shielding layer comprising a thin film of a metal such as chromium, nickel or aluminum, or a light-shielding layer comprising a binder resin and a pigment such as carbon black or titanium oxide dispersed in the binder resin is provided on the non-picture-element area of a color filter useful for liquid crystal displays or the like in order to increase the contrast of images displayed.
However, the above-described conventional light-shielding layers are electrically conductive, so that they have the following problems: it is necessary to separately provide an insulating layer when either one of the light-shielding layers is provided between transparent electrode layers; the light-shielding layers tend to cause short circuiting between electrode layers; and cross talk between electrode layers which are adjacent to each other through the conductive light-shielding layer is increased. Further, in the case where a non-conductive light-shielding layer is provided by dispersing a non-conductive inorganic pigment such as titanium oxide in a binder resin, there exists such a problem that the pigment cannot be easily dispersed in the binder resin because the particle diameter of the pigment is large. In addition, the resulting light-shielding layer (coating layer) is insufficient in blackness.
An object of the present invention is therefore to provide a composition suitable for forming a light-shielding layer that is excellent in both light-shielding properties and blackness and that is not electrically conductive, and a non-conductive light-shielding layer formed from the composition.